Linear extrusion and rotational sweeping are among the simplest and the. Even lacking a picture of an object, a program that quickly builds 3D data from a library of potential shapes would speed up the 3D design process, particularly for people without years of training and practice with CAD programs. The object modeling with sweeping has been extensively used in 3D data modeling 3. So how does this program help 3D design? Every part is made up of basic shapes. The program also has difficulty picking out edges of fuzzy materials, or objects with a lot of shadows or a soft background, as is the case with the aforementioned Photoshop reference. Objects that aren’t completely visible can’t be modeled, and objects that suddenly change the type of shape involved (such as a toothpaste container) don’t build proper 3D models. Theres this video that demonstrates modeling a globoid worm gear. The extrusion path will act as a guide for sweeping the cross section along it. The extruded cross section must be defined perpendicular to the path of extrusion. Like any newly developed program, the process isn’t perfect. Figure 9 Examples of Solid modeling 4.3 Sweep In this technique, the path of the extrusion must be defined (trajectory). The computer reshapes the component to fit the image of the object in the photograph as well as to satisfy various inferred geometric constraints imposed by its global 3D structure.
In our interface, three strokes are used to generate a 3D component that snaps to the shape’s outline in the photograph, where each stroke defines one dimension of the component. Sweeps are used to create models like pipes, tubbing, drain pipes, gasket grooves, and threads.
If the profile is an open object, the sweep will create a surface. If the profile is a closed object, the sweep will create a solid. Our technique provides the user the means to quickly create editable 3D parts- human assistance implicitly segments a complex object into its components, and positions them in space. The path can be an open or closed drawing object but must be one object. Ariel Shamir explains how humans can help the machines: Once the 3D object has been extracted, it can be quickly edited and placed back into photos or 3D scenes, permitting object-driven photo editing tasks which are impossible to perform in image-space. As anyone who has ever used Photoshop could testify, computers aren’t great at grabbing the proper information from pictures without help. We show that this intelligent interactive modeling tool provides the means to create editable 3D parts quickly. It begins by briefly describing the issues in 3D object modeling and their impact on the quality of the resulting model. Dubbed 3-Sweep by the research team, the system uses both computer and user generated data to build 3D objects. This chapter provides an overview of 3D object modeling approaches. The cooperative research has developed a method of pulling 3D designs from 2D images that has potential for improving both current and future 3D design.